Spacecraft Plasma Interaction eXperiment in India: An introduction

Possibility of arcing in high voltage arrays have necessitated the theoretical and experimental study of charging and arcing by Indian Space Research Organisation (ISRO), which is planning to increase the satellite bus voltage above the current level of 42 volt. The study, named Spacecraft Plasma Interaction eXperiment (SPIX) was undertaken, together with Institute for Plasma Research (IPR), India to (1) develop software, which is able to predict the floating potential of an object of simplified geometry in space plasma typically of geosynchronous bimaxwellian type, which is also able to calculate the differential potential between two such objects, (2) to develop software to solve the differential equations describing primary arcing phenomena developed by Cho, a pioneer in the field, (3) to study the primary arcing threshold and frequency and to identify the arcing sites of a solar array coupon immersed in a LEO (Low Earth Orbit) like laboratory plasma and to (4) find out the arcing threshold of sustained arcs by introducing a solar array simulator voltage between adjacent strings in a solar array coupon immersed in a LEO-like plasma environment. The experiments have largely yielded results akin to that of other investigators, although some differences have been observed in some experiments. A short term future aim would be to increase the sample space in the last type of experiments mentioned above.